Difference between revisions of "Observables"

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6.) Switch from pol to unpol frequently <br>
 
6.) Switch from pol to unpol frequently <br>
  
For unpolarized electron beam:<br>
+
For unpolarized electron beam the helicity dependent cross sections are: <br>  
 
[[Image:2.png|180px]]
 
[[Image:2.png|180px]]
[[Image:3.png|150px]]
+
[[Image:3.png|150px]]<br>
 +
Where in the deuteron rest frame the spin is quantized in the direction of the virtual photon<br>
  
Which means there is a direct relationship to first component analyzing power<br>
+
This means there is a direct relationship to first component analyzing power<br>
  
[[Image:2.png|230px]]
+
[[Image:0.png|230px]]
  
which is very much accessible with e+D->e+N+X <br>
+
which is very much accessible with e+D->e+N+X and e+D->e+X (be weary of background) <br>
 +
Modern (2006) Thesis [http://blast.lns.mit.edu/PUBLIC_RESULTS/THESES/Zhang_thesis.pdf] <br>
  
In addition we have a direct relationship to b1 for low x but be weary uncertainties<br>
+
In addition we have a direct relationship to b1 for low x (be weary uncertainties) <br>
  
 
[[Image:5.png|200px]]
 
[[Image:5.png|200px]]

Latest revision as of 14:15, 25 April 2013

A couple of words about Axx and how to measure it:

1.png

Axx is an asymmetry so take advantage of numerator denominator systematics cancellation:

1.) Measure Np and Nu with same cup same exact material
2.) Use same B-field
3.) Use NMR on both to measure polarization and un-polarization
4.) Let beam heating an off larmor microwave control un-polarization
5.) Keep both cold (~1K)
6.) Switch from pol to unpol frequently

For unpolarized electron beam the helicity dependent cross sections are:
2.png 3.png
Where in the deuteron rest frame the spin is quantized in the direction of the virtual photon

This means there is a direct relationship to first component analyzing power

0.png

which is very much accessible with e+D->e+N+X and e+D->e+X (be weary of background)
Modern (2006) Thesis [1]

In addition we have a direct relationship to b1 for low x (be weary uncertainties)

5.png